J Vet Sci.  2008 Dec;9(4):407-413. 10.4142/jvs.2008.9.4.407.

Three-dimensional CT angiography of the canine hepatic vasculature

• Jeong Y
• Lim C
• Oh S
• Jung J
• Chang J
• Yoon J
• Choi M

• KMID: 1104917
• DOI: http://doi.org/10.4142/jvs.2008.9.4.407

Abstract

Eight Beagle dogs were anesthetized and were imaged using a single channel helical CT scanner. The contrast medium used in this study was iohexol (300 mg I/ml) and doses were 0.5 ml/kg for a cine scan, 3 ml/kg for an enhanced scan. The flow rate for contrast material administration was 2 ml/sec for all scans. This study was divided into three steps, with unenhanced, cine and enhanced scans. The enhanced scan was subdivided into the arterial phase and the venous phase. All of the enhanced scans were reconstructed in 1 mm intervals and the scans were interpreted by the use of reformatted images, a cross sectional histogram, maximum intensity projection and shaded surface display. For the cine scans, optimal times were a 9-sec delay time post IV injection in the arterial phase, and an 18-sec delay time post IV injection in the venous phase. A nine-sec delay time was acceptable for the imaging of the canine hepatic arteries by CT angiography. After completion of arterial phase scanning, venous structures of the liver were well visualized as seen on the venous phase.

Keyword

angiography; computed tomography; dual phase; liver vasculature; three-dimensional image

MeSH Terms

Angiography/methods/*veterinary
Animals
Contrast Media/pharmacology
Dogs/*anatomy & histology
Iohexol/pharmacology
Liver/*blood supply
Tomography, X-Ray Computed/methods/*veterinary

Figure

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  Fig. 1 A time-attenuation graph. On cine scan images, the region of interest (ROI) was set up in the center of the aorta, and then a time-attenuation graph was constructed from the ROI.

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  Fig. 2 The delay time was confirmed in the aorta through a time-attenuation graph. The threshold (dash arrow) was baseline Hounsfield unit value (open arrow) added on 20 Hounsfield unit (HU). The delay time (arrow) was the first time that exceeded over this threshold.

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  Fig. 3 Each vessel was confirmed anatomical location through shaded surface display (SSD), maximum intensity projection (MIP), axial and oblique images (A and B). Rt. hepatic a. branch (arrows), Lt. Lateral hepatic vein (arrowheads).

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  Fig. 4 Hepatic vascular structures in three-dimensional (3D) shaded surface display images (A-H). Figs. A and B are arterial 3D structures. Figs. C-H are portal and hepatic venous 3D structures (1 = aorta; 2 = celiac a.; 3 = hepatic a.; 4 = cranial mesenteric a.; 5 = left gastric a.; 6 = right gastric a.; 7 = gastroduodenal a.; 8 = right hepatic a. branch; 9 = left hepatic a. branch; 10 = main portal v.; 11 = cranial mesenteric v.; 12 = caudal mesenteric v.; 13 = right kidney; 14 = left kidney; 15 = gastroduodenal v.; 16 = caudate portal v.; 17 = right lateral portal v.; 18 = right medial portal v.; 19 = gall bladder; 20 = right medial hepatic v.; 21 = quadrate hepatic v.; 22 = papillary hepatic v.; 23 = quadrate portal v.; 24 = left medial portal v.; 25 = left lateral portal v.; 26 = left lateral hepatic v.; 27 = caudal vena cava; 28 = caudate hepatic v.; 29 = right lateral hepatic v.; 30 = left medial hepatic v.; 31 = papillary portal v.).

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  Fig. 5 Average pixel intensity values were measured by defined area (arrows).

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